Methine dyes and preparation thereof

ABSTRACT

Methine dyes (I) which conform in one of their tautomeric forms to the general formula ##STR1## where Y 1  is in both or either case an electron-attracting group and the other Y 1  is hydrogen, 
     Y 2  is in each case, independently of the others, hydrogen, --CN, halogen, C 1  -C 6  -alkyl, C 5  -C 7  -cycloalkyl, phenyl, pyridyl or together with a further Y 2  a five- or six-membered ring which may have a fused-on benzene ring, 
     R is hydrogen, C 1  -C 20  -alkyl, C 7  -C 10  -aralkyl or β-hydroxyethyl and 
     n is 1, 2, 3, 4, 5 or 6 and the groups ##STR2##  are identical or different five- or six-membered heterocyclic radicals, except 1,2,4-oxadiazol-5-yl, and the radicals D may be substituted and/or fused and can be present in the quaternized (cationic) or deprotonated (anionic) form, the compounds of the formulae ##STR3## being excepted, have a very high molar absorption within the range from 500 to 1200 nm and are in many cases readily soluble in organic solvents and/or thermoplastics or crosslinked plastics, which is why these dyes are highly suitable for optical recording media; a process for preparing (I); and optical recording media which contain (I).

Neutral methine dyes which contain a 1,2,4-oxadiazole nucleus and, onthe α-carbon of the methine chain, an electron-attracting radical areknown from British Patent No. 626,470. Symmetrical quaternarypentamethine dyes with N-methyl- and N-ethylbenzothiazole andelectron-attracting radicals on the α-carbon are known from GermanLaid-Open Application Nos. DOS 2,142,967, DOS 2,165,915 and DOS2,214,055.

The present invention relates to methine dyes which, in one of theirtautomeric forms, have the general formula ##STR4## where Y¹ is in bothor either case an electron-attracting group and the other Y¹ ishydrogen,

Y² is in each case, independently of the others, hydrogen, cyano,halogen, C₁ -C₆ -alkyl, C₅ -C₇ -cycloalkyl, phenyl, pyridyl or togetherwith a further Y² a five- or six-membered ring which may have a fused-onbenzene ring,

R is hydrogen, C₁ -C₂₀ -alkyl, C₇ -C₁₀ -aralkyl or β-hydroxyethyl and

n is 1, 2, 3, 4, 5 or 6 and the groups ##STR5## are identical ordifferent five- or six-membered heterocyclic radicals, except1,2,4-oxadiazol-5-yl, and the radicals D may be substituted and/or fusedand can be present in the quaternized (cationic) or deprotonated(anionic) form, the compounds of the formulae ##STR6## where X.sup.⊖ isone equivalent of an anion, being excepted.

The methine dyes (I) of the invention have a very high molar absorptionwithin the range from 500 to 1200 nm. Many are readily soluble inorganic solvents, thermoplastics or crosslinked plastics.Correspondingly the optical recording media obtainable with the methinedyes (I) are of high quality, having for example a high visual contrast,a very high signal-to-noise ratio and a favorable threshold energy.

Suitable electron-attracting groups Y¹ are cyano, trifluoromethyl,nitro, carbo-C₁ -C₁₂ -alkoxy or phenylsulfonyl which may bemonosubstituted or disubstituted by C₁ -C₁₂ -alkyl, C₁ -C₁₂ -alkoxy,halogen and/or cyano. Y¹ is preferably cyano. ##STR7## are derivedfrom 1. substituted or unsubstituted 5-membered rings which carry in theα-position relative to the point of attachment an N atom and, ifdesired, 1 or 2 further hetero atoms--except 1,2,4-oxadiazol-5-yl, and

2. substituted or unsubstituted 6-membered rings which carry in theα-position relative to the point of attachment an N atom and, ifdesired, 1 or 2 further N atoms,

and the 5- and 6-membered heterocyclic rings can be fused to benzene ornaphthalene rings.

D is derived for example from

1.1 thiazole, selenazole, oxazole, imidazole, isoxazole, isothiazole,isoselenazole, pyrazole, 1,2,4-thiadiazole, 1,2,4-selenadiazole,1,2,4-triazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole, 1,2,5-oxadiazole,1,2,5-thiadiazole, 1,2,3-triazole, 1,2,5-selenadiazole,1,3,4-selenadiazole;

1.2 benzoxazole, benzothiazole, benzoselenazole, benzimidazole,benzisoxazole, indole, benzisothiazole, benzisoselenazole,benzopyrazole;

1.3 the compounds of 1.1 with a fused-on 1,2- and 2,3-naphthalenesystem.

2.1 Pyridine, pyrimidine, pyrazine, 1,2,4-triazine, pyridazine;

2.2 quinoline, quinazoline, quinoxaline;

2.3 the compounds of 2.1 with a fused-on 1,2- and 2,3-naphthalenesystem.

Specific examples of ##STR8## are: ##STR9##

In the above formulae, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹ andR¹² are each, independently of one another, hydrogen, halogen, CN, CF₃,nitro, C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy or phenyl which may be substitutedby halogen, C₁ -C₄ -alkyl, C₁ -C₄ -alkoxy, CN, CF₃ and/or NO₂, only onenitro group being present per radical D.

Suitable halogen is bromine, fluorine and preferably chlorine.

Specific examples of C₁ -C₄ -alkyl are: methyl, ethyl, n-propyl,iso-propyl, n-butyl, sec.-butyl, isobutyl and tert.-butyl.

Specific examples of C₁ -C₄ -alkoxy are: methoxy, ethoxy, propoxy,isopropoxy, butoxy, 2-butoxy and tert.-butoxy.

The number of substituents on D is, per D, up to 4, preferably 0, 1 or2, in particular 0 or 1.

Preferred methine dyes (II) are those of the formula ##STR10## where Y³is cyano and

Y² and Y⁴ are each, independently of one another, hydrogen, chlorine,cyano, phenyl or pyridyl or together a five- or six-membered ring whichmay have a fused-on benzene nucleus, and n is 1, 2, 3, 4, 5 or 6, and D'is derived from benzothiazole, benzoselenazole, benzoxazole,benzimidazole, pyridine, pyrimidine, pyrazine, pyridazine, quinoline,quinoxaline, indole or quinazoline, the two radicals D' being identicalor different, and R has the abovementioned meanings.

Preferred specific examples of D' are: ##STR11## where R³ is --H, --CH₃,--C₂ H₅, --n--C₄ H₉, --C₈ H₁₇, C₁₂ H₂₅, C₁₆ H₃₅, --C₁₈ H₃₇ or --C₂₀ H₄₁; ##STR12##

Particular preference is given to methine dyes of the formula (III)##STR13## where D", A, Y⁵, Y⁷ and R have the meanings indicated in Table1.

    TABLE 1      Dye the one       No. D" the other D" R  Y.sup.5 Y.sup.7 [A]               III.      1     ##STR14##      ##STR15##      H  CN CN      ##STR16##       III.  2 " " C.sub.2 H.sub.5  " " " III.  3 " " n-C.sub.4 H.sub.9  " "     " III.  4 " " C.sub.12 H.sub.25 (n)  " " "  III.      5 " "  H  " "     ##STR17##       III.  6 " " C.sub.2 H.sub.5  " " " III.  7 " " n-C.sub.4 H.sub.9  " "     " III.  8 " " C.sub.12 H.sub.25 (n)  " " "  III.      9 " " H  " "     ##STR18##       III.  10 " " C.sub.2 H.sub.5  " " " III.  11 " " n-C.sub.4 H.sub.9  "     " " III.  12 " " C.sub.12 H.sub.25 (n)  " " "  III.  13 " "  H  " "      ##STR19##       III.  14 " " C.sub.2 H.sub.5  " " " III.  15 " " n-C.sub.4 H.sub.9  "     " " III.  16 " " C.sub.12 H.sub.25 (n)  " " "  III.      17     ##STR20##      ##STR21##      H R.sup.3 =      H " "     ##STR22##        III.  18 " " " R.sup.3 =  CH.sub.3 " " " III.  19 " " " R.sup.3 =     C.sub.2 H.sub.5 " " " III.  20 " " " R.sup.3 = C.sub.12 H.sub.25 (n) " "     " III.  21 " " C.sub.2 H.sub.5 R.sup.3 = H " " " III.  22 " " " R.sup.3     = CH.sub.3 " " " III.  23 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  24     " " " R.sup.3 = C.sub.12 H.sub.25 (n) " " " III.  25 " " n-C.sub.4     H.sub.9 R.sup.3 = H " " " III.  26 " " " R.sup.3 =  CH.sub.3 " " " III.     27 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  28 " " C.sub.4 H.sub.9     R.sup.3 = C.sub.12 H.sub.25 (n) " " "  III.  29 " " H R.sup.3 = H " "      ##STR23##       III.  30 " " " R.sup.3 = CH.sub.3 " " " III.  31 " " " R.sup.3 =     C.sub.2 H.sub.5 " " " III.  32 " " " R.sup.3 = C.sub.12 H.sub.25 (n) " "     " III.  33 " " C.sub.2 H.sub.5 R.sup.3 = H " " " III.  34 " " " R.sup.3     = CH.sub.3 " " " III.  35 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  36     " " " R.sup.3 = C.sub.12 H.sub.25 (n) " " " III.  37 " " n-C.sub.4     H.sub.9 R.sup.3 = H " " " III.  38 " " " R.sup.3 = CH.sub.3 " " " III.     39 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  40 " " " R.sup.3 =     C.sub.12 H.sub.25 (n) " " "  III.  41 " " H R.sup.3 =       H " "     ##STR24##       III.  42 " " " R.sup.3 = CH.sub.3 " " " III.  43 " " " R.sup.3 =     C.sub.2 H.sub.5 " " " III.  44 " " " R.sup.3 = C.sub.12 H.sub.25 (n) " "     " III.  45 " " C.sub.2 H.sub.5 R.sup.3 = H " " " III.  46 " " " R.sup.3     = CH.sub.3 " " " III.  47 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  48     " " " R.sup.3 = C.sub.12 H.sub.25 (n) " " " III.  49 " " n-C.sub.4     H.sub.9 R.sup.3 = H " " " III.  50 " " " R.sup.3 = CH.sub.3 " " " III.     51 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  52 " " " R.sup.3 =     C.sub.12 H.sub.25 (n) " " "  III.  53 " " H R.sup.3 =      H " "     ##STR25##       III.  54 " " " R.sup.3 = CH.sub.3 " " " III.  55 " " " R.sup.3 =     C.sub.2 H.sub.5 " " " III.  56 " " " R.sup.3 = C.sub.12 H.sub.25 (n) " "     " III.  57 " " C.sub.2 H.sub.5 R.sup.3 = H " " " III.  58 " " " R.sup.3     = CH.sub.3 " " " III.  59 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  60     " " " R.sup.3 = C.sub.12 H.sub.25 (n) " " " III.  61 " " n-C.sub.4     H.sub.9 R.sup.3 = H " " " III.  62 " " " R.sup.3 = CH.sub.3 " " " III.     63 " " " R.sup.3 = C.sub.2 H.sub.5 " " " III.  64 " " C.sub.4 H.sub.9     R.sup.3 = C.sub.12 H.sub.25 (n) " " "  III.      65     ##STR26##      ##STR27##      H R.sup.7 = HR.sup.8 =      H " "     ##STR28##       III.  66 " " " R.sup.7 = H " " "     R.sup.8 = CH.sub.3 III.  67 " " "     R.sup.7 = CH.sub.3 " " "     R.sup.8 = CH.sub.3  III.  68 " " " R.sup.7     = H R.sup.8 =      H " "     ##STR29##       III.  69 " " " R.sup.7 = H " " "     R.sup.8 = CH.sub.3 III.  70 " " "     R.sup.7 = CH.sub.3 " " "     R.sup.8 = H  III.  71 " " " R.sup.7 =     HR.sup.8 =      H " "     ##STR30##        III.  72 " " " R.sup.7 = H " " "     R.sup.8 =  CH.sub.3 III.  73 " "     " R.sup.7 = CH.sub.3 " " "     R.sup.8 = H  III.  74 " " " R.sup.7 =     HR.sup.8 =      H " "     ##STR31##        III.  75 " " " R.sup.7 = H " " "     R.sup.8 = CH.sub.3 III.  76 " "     " R.sup.7 = CH.sub.3 " " "     R.sup.8 = H  III.      77     ##STR32##      ##STR33##      "  " "      ##STR34##       III.  78 " " C.sub.2 H.sub.5  " " "  III.      79 " " H  " "     ##STR35##       III.  80 " " C.sub.2 H.sub.5  " " "  III.      81 " " H  " "     ##STR36##       III.  82 " " C.sub.2 H.sub.5  " " "  III.      83 " " H  " "     ##STR37##       III.  84 " " C.sub.2 H.sub.5  " " "  III.      85     ##STR38##      ##STR39##      H R.sup.7 = HR.sup.8 =      H " "     ##STR40##       III.  86 " " " R.sup.7 = H " " "     R.sup.8 = CH.sub.3 III.  87 " " "     R.sup.7 = CH.sub.3 " " "     R.sup.8 = CH.sub.3  III.      88     ##STR41##      ##STR42##      " R.sup.4 =      H " "     ##STR43##       III.  89 " " CH.sub.3 R.sup.4 = H " " " III.  90 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III.  91 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III.      92 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.  93 " " H R.sup.4 = C     H.sub.3 " " " III.  94 " " CH.sub.3 R.sup.4 = CH.sub.3 " " " III.  95 "     " C.sub. 2 H.sub.5 R.sup.4 = CH.sub.3 " " " III.  96 " " C.sub.2 H.sub.4     OH R.sup.4 = CH.sub.3 " " " III.  97 " " C.sub.12 H.sub.25 (n) R.sup.4 = C     H.sub.3 " " "  III.      98     ##STR44##      ##STR45##      H R.sup.4 =      H " "     ##STR46##       III.  99 " " CH.sub.3 R.sup.4 = H " " " III. 100 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 101 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III.     102 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III. 103 " " H R.sup.4 = C     H.sub.3 " " " III. 104 " " CH.sub.3 R.sup.4 = CH.sub.3 " " " III. 105 "     " C.sub.2 H.sub.5 R.sup.4 = CH.sub.3 " " " III. 106 " " C.sub.2 H.sub.4     OH R.sup.4 = CH.sub.3 " " " III. 107 " " C.sub.12 H.sub.25 (n) R.sup.4 = C     H.sub.3 " " "  III. 108 " " H R.sup.4 =      H " "     ##STR47##       III. 109 " " CH.sub.3 R.sup.4 = H " " " III. 110 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 111 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III.     112 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III. 113 " " H R.sup.4 = C     H.sub.3 " " " III. 114 " " CH.sub.3 R.sup.4 = CH.sub.3 " " " III. 115 "     " C.sub.2 H.sub.5 R.sup.4 = CH.sub.3 " " " III. 116 " " C.sub.2 H.sub.4     OH R.sup. 4 = CH.sub.3 " " " III. 117 " " C.sub.12 H.sub.25 (n) R.sup.4     = CH.sub.3 " " "  III. 118 " " H R.sup.4 =      H " "     ##STR48##       III. 119 " " CH.sub.3 R.sup.4 = H " " " III. 120 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 121 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III.     122 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III. 123 " " H R.sup.4 = C     H.sub.3 "  " " III. 124 " " CH.sub.3 R.sup.4 = CH.sub.3 " " " III. 125 "     " C.sub.2 H.sub.5 R.sup.4 = CH.sub.3 " " " III. 126 " " C.sub.2 H.sub.4     OH R.sup.4 = CH.sub.3 " " " III. 127 " " C.sub.12 H.sub.25 (n) R.sup.4 = C     H.sub.3 " " "      III. 128     ##STR49##      ##STR50##      H R.sup.4 =      H " "     ##STR51##       III. 129 " " " R.sup.4 = CH.sub.3 " " " III. 130 " "  CH.sub.3 R.sup.4     = H " " " III. 131 " " " R.sup.4 = CH.sub.3 " " " III. 132 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 133 " " " R.sup.4 = CH.sub.3 " " " III.     134 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 135 " " H R.sup.4 =     CH.sub.3 " " " III. 136 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     137 " " " R.sup.4 = CH.sub.3 " " "      III. 138     ##STR52##      ##STR53##      H R.sup.4 = HR.sup.5 = HR.sup.10 =      H " "     ##STR54##       III. 139 " " " R.sup.4 = CH.sub.3 " " "     R.sup.5 = CH.sub.3     R.sup.10 = H III. 140 " " " R.sup.4 = H " " "     R.sup.5 = CH.sub.3     R.sup.10 = H III. 141 " " " R.sup.4 = CH.sub.3 " " "     R.sup.5 =     CH.sub.3     R.sup.10 = CN  III. 142 " " " R.sup.4 = HR.sup.5 =      CH.sub.3R.sup.10 =      H " "     ##STR55##        III. 143 " " " R.sup.4 = CH.sub.3 " " "     R.sup.5 = CH.sub.3     R.sup.10 = H III. 144 " " " R.sup.4 = H " " "     R.sup.5 = H     R.sup.10 = CN III. 145 " " " R.sup.4 = CH.sub.3 " " "     R.sup.5 =     CH.sub.3     R.sup.10 = CN  III. 146 " " " R.sup.4 = HR.sup.5 =      HR.sup.10 =      H " "     ##STR56##       III. 147 " " " R.sup.4 = CH.sub.3 " " "     R.sup.5 = CH.sub.3     R.sup.10 = H III. 148 " " " R.sup.4 = H " " "     R.sup.5 = CH.sub.3     R.sup.10 = H III. 149 "  " " R.sup.4 = CH.sub.3 " " "     R.sup.5 =     CH.sub.3     R.sup.10 = CN  III. 150 " " " R.sup.4 = HR.sup.5 =      HR.sup.10 =      H " "     ##STR57##       III. 151 " " " R.sup.4 = CH.sub.3 " " "     R.sup.5 = CH.sub.3     R.sup.10 = H III. 152 " " " R.sup.4 = H " " "     R.sup.5 = H     R.sup.10 = CN III. 153 " "  " R.sup.4 = CH.sub.3 " " "     R.sup.5 =     CH.sub.3     R.sup.10 = CN      III. 154     ##STR58##      ##STR59##      " R.sup.4 =      H " "     ##STR60##       III. 155 " " " R.sup.4 = CH.sub.3 " " " III. 156 " " CH.sub.3 R.sup.4     = H " " " III. 157 " " " R.sup.4 = CH.sub.3 " " " III. 158 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 159 " " " R.sup.4 =  CH.sub.3 " " "  III.     160      ##STR61##      ##STR62##      H R.sup.4 =      H " "     ##STR63##       III. 161 " " " R.sup.4 = CH.sub.3 " " " III. 162 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 163 " " " R.sup.4 = CH.sub.3 " " " III. 164 " "     n-C.sub.4 H.sub.9 R.sup.4 = H " " " III. 165 " " C.sub.4 H.sub.9 R.sup.4     =  CH.sub.3 " " " III. 166 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " "     III. 167 " " " R.sup.4 = CH.sub.3 " " "  III. 168 " " H R.sup.4 = H " "      ##STR64##       III. 169 " " " R.sup.4 = CH.sub.3 " " " III. 170 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 171 " " " R.sup.4 = CH.sub.3 " " " III. 172 " "     n-C.sub.4 H.sub.9 R.sup.4 = H " " " III. 173 " " C.sub.4 H.sub.9 R.sup.4     = CH.sub.3 " " " III. 174 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " "     III. 175 " " " R.sup.4 = CH.sub.3 " " "  III. 176 " " H R.sup.4 = H " "      ##STR65##       III. 177 " " " R.sup.4 = CH.sub.3 " " " III. 178 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 179 " " " R.sup.4 = CH.sub.3 " " " III. 180 " "     n-C.sub.4 H.sub.9 R.sup.4 =  H " " " III. 181 " " C.sub.4 H.sub.9     R.sup.4 = CH.sub.3 " " " III. 182 " " C.sub.12 H.sub.25 (n) R.sup.4 = H     " " " III. 183 " " " R.sup.4 = CH.sub.3 " " "  III. 184 " " H R.sup.4 =     H " "      ##STR66##       III. 185 " " " R.sup.4 = CH.sub.3 " " " III. 186 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 187 " " " R.sup.4 = CH.sub.3 " " " III. 188 " "     n-C.sub.4 H.sub.9 R.sup.4 = H " " " III. 189 " " C.sub.4 H.sub.9 R.sup.4     = CH.sub.3 " " " III. 190 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " "     III. 191 " " " R.sup.4 = CH.sub.3 " " "      III. 192 "     ##STR67##      H R.sup.3 = HR.sup.4 =      H " "     ##STR68##       III. 193 " " " R.sup.3 = H " " "     R.sup.4 =  CH.sub.3 III. 194 " "     " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 195 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 196 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 197 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3 III. 198 " " C.sub.2 H.sub.5 R.sup.3 = H " "     "     R.sup.4 = H III. 199 " " " R.sup.3 = H " " "     R.sup.4 =     CH.sub.3 III. 200 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III.     201 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 202 " " "     R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H III. 203 " " " R.sup.3 = C     .sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3 III. 204 " " n-C.sub.4     H.sub.9 R.sup.3 = H " " "     R.sup.4 = H III. 205 " " " R.sup.3 = H " "     "     R.sup.4 = CH.sub.3 III. 206 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 207 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 =     CH.sub.3 III. 208 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H     III. 209 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3     III. 210 " " C.sub.8 H.sub.17 (n) R.sup.3 = H " " "     R.sup.4 = H III.     211 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 212 " " "     R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 213 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 214 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 215 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3  III. 216 " " H R.sup.3 = HR.sup.4 = H " "      ##STR69##       III. 217 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 218 " " "     R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 219 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 220 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 221 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3 III. 222 " " C.sub.2 H.sub.5 R.sup.3 = H " "     "     R.sup.4 = H III. 223 " " " R.sup.3 = H " " "     R.sup.4 =     CH.sub.3 III. 224 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III.     225 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 226 " " "     R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H III. 227 " " " R.sup.3 = C     .sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3 III. 228 "  " n-C.sub.4     H.sub.9 R.sup.3 = H " " "     R.sup.4 = H III. 229 " " " R.sup.3 = H " "     "     R.sup.4 = CH.sub.3 III. 230 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 231 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 =     CH.sub.3 III. 232 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H     III. 233 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 =  CH.sub.3     III. 234 " " C.sub.8 H.sub.17 (n) R.sup.3 = H " " "     R.sup.4 = H III.     235 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 236 " " "     R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 237 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 238 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 239 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3  III. 240 " " H R.sup.3 = HR.sup.4 = H " "      ##STR70##       III. 241 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 242 " " "     R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 243 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 244 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 =  H III. 245 " " " R.sup.3 = C.sub.2 H.sub.5     " " "     R.sup.4 = CH.sub.3 III. 246 " " C.sub.2 H.sub.5 R.sup.3 = H "     " "     R.sup.4 = H III. 247 " " " R.sup.3 = H " " "     R.sup.4 =     CH.sub.3 III. 248 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III.     249 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 250 " " "     R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H III. 251 " " " R.sup.3 = C     .sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3 III. 252 " "  n-C.sub.4     H.sub.9 R.sup.3 = H " " "     R.sup.4 = H " " " III. 253 " " " R.sup.3 = H      " " "     R.sup.4 = CH.sub.3 III. 254 " " " R.sup.3 = CH.sub.3 " " "      R.sup.4 = H III. 255 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 =     CH.sub.3 III. 256 " " " R.sup.3 =  C.sub.2 H.sub.5 " " "     R.sup.4 = H     III. 257 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3     III. 258 " " C.sub.8 H.sub.17 (n) R.sup.3 = H " " "     R.sup.4 = H III.     259 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 260 " " "     R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 261 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 262 " " "  R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 263 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3   III. 264 " " H R.sup.3 = HR.sup.4 = H " "      ##STR71##        III. 265 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 266 " "     " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 267 " " " R.sup.3  =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 268 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 269 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3 III. 270 " " C.sub.2 H.sub.5 R.sup.3 = H " "     "     R.sup.4 = H III. 271 " " " R.sup.3 = H " " "     R.sup.4 =     CH.sub.3 III. 272 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III.     273 " "  " R.sup.3 = CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 274 " "     " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H III. 275 " " " R.sup.3     = C.sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3 III. 276 " " n-C.sub.4     H.sub.9 R.sup.3 = H " " "     R.sup.4 = H III. 277 " " " R.sup.3 = H " "     "     R.sup.4 = CH.sub.3 III. 278 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 =  H III. 279 " " " R.sup.3 = CH.sub.3 " " "     R.sup.4 =     CH.sub.3 III. 280 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = H     III. 281 " " " R.sup.3 = C.sub.2 H.sub.5 " " "     R.sup.4 = CH.sub.3     III. 282 " " C.sub.8 H.sub.17 (n) R.sup.3 = H " " "     R.sup.4 = H III.     283 " " " R.sup.3 = H " " "     R.sup.4 = CH.sub.3 III. 284 " " "     R.sup.3 = CH.sub.3 " " "     R.sup.4 = H III. 285 " " " R.sup.3 =     CH.sub.3 " " "     R.sup.4 = CH.sub.3 III. 286 " " " R.sup.3 = C.sub.2     H.sub.5 " " "     R.sup.4 = H III. 287 " " " R.sup.3 = C.sub.2 H.sub.5 "     " "     R.sup.4 = CH.sub.3      III. 288     ##STR72##      ##STR73##      H R.sup.4 = HR.sup.7 =      H " "     ##STR74##       III. 289 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 290 " " "     R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 291 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 292 " " CH.sub.3 R.sup.4 = H     " " "     R.sup.7 = H III. 293 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 294 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III.     295 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 296 " "     C.sub.2 H.sub.5 R.sup.4 = H " " "     R.sup.7 = H III. 297 " " " R.sup.4     = CH.sub.3 " " "     R.sup.7 = H III. 298 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 299 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = C     H.sub.3 III. 300 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " "     R.sup.7 =  H      III. 301 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 302 " " "     R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 303 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 304 " " C.sub.8 H.sub.17 (n)     R.sup.4 = H " " "     R.sup.7 = H III. 305 " " " R.sup.4 = CH.sub.3 " "     "     R.sup.7 = H III. 306 " " " R.sup.4 = H " " "     R.sup.7  =     CH.sub.3 III. 307 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3     III. 308 " " H R.sup.4 = HR.sup.7 =      H " "     ##STR75##           R.sup.7 = H III. 309 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 =     H III. 310 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 311 " " "     R.sup.4 = CH.sub.3 " " "     R.sup. 7 = CH.sub.3 III. 312 " " CH.sub.3     R.sup.4 = H " " "     R.sup.7 = H III. 313 " " " R.sup.4 = CH.sub.3 " "     "     R.sup.7 = H III. 314 " " " R.sup.4 = H " " "     R.sup.7 =     CH.sub.3 III. 315 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3     III. 316 " " C.sub.2 H.sub.5 R.sup.4 = H " " "     R.sup.7 = H III. 317     " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 318 " " " R.sup.4 =     H " " "     R.sup.7 = CH.sub.3 III. 319 " " " R.sup.4 = CH.sub.3 " " "       R.sup.7 = CH.sub.3 III. 320 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " "       R.sup.7 = H III. 321 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H     III. 322 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 323 " " "     R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 324 " " C.sub.8     H.sub.17 (n) R.sup.4 = H " " "     R.sup.7 = H III. 325 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = H III. 326 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 327 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = C     H.sub.3  III. 328 " " H R.sup.4 = HR.sup.7 =      H " "     ##STR76##       III. 329 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 330 " " "     R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 331 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 332 " " CH.sub.3 R.sup.4 = H     " " "     R.sup.7 = H III. 333 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 334 " " " R.sup.4 = H " " "     R.sup.7 =  CH.sub.3     III. 335 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 336     " " C.sub.2 H.sub.5 R.sup.4 = H " " "     R.sup.7 = H III. 337 " " "     R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 338 " " " R.sup.4 = H " "     "     R.sup.7 = CH.sub.3 III. 339 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 340 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " "     R.sup.7 = H III. 341 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III.     342 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 343 " " "     R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 344 " " C.sub.8     H.sub.17 (n) R.sup.4 = H " " "     R.sup.7 = H III. 345 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = H III. 346 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 347 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = C     H.sub.3  III. 348 " " H R.sup.4 = HR.sup.7 =      H " "     ##STR77##        III. 349 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 350 " "     " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 351 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 =  CH.sub.3 III. 352 " " CH.sub.3 R.sup.4 = H     " " "     R.sup.7 = H III. 353 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 354 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III.     355 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 356 " "     C.sub.2 H.sub.5 R.sup.4 = H " " "     R.sup.7 = H III. 357 " " " R.sup.4     = CH.sub.3 " " "     R.sup.7 =  H III. 358 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 359 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = C     H.sub.3 III. 360 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " "     R.sup.7 =     H III. 361 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 362 " " "     R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 363 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 364 " " C.sub.8 H.sub.17 (n)     R.sup.4 = H " " "     R.sup.7 = H III. 365 " " " R.sup.4 = CH.sub.3 " "     "     R.sup.7 = H III. 366 " " " R.sup.4 = H " " "     R.sup.7 =     CH.sub.3 III. 367 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3     III. 368 " " H R.sup.4 = HR.sup.7 =      H " "     ##STR78##        III. 369 " " " R.sup.4 =  H " " "     R.sup.7 = CH.sub.3 III. 370 " "     " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 371 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 372 " " CH.sub.3 R.sup.4 = H     " " "     R.sup.7 = H III. 373 " " " R.sup.4 = H " " "     R.sup.7 =     CH.sub.3 III. 374 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III.     374a " " " R.sup.4 = CH.sub. 3 " " "     R.sup.7 = H III. 375 " "     C.sub.2 H.sub.5 R.sup.4 = H " " "     R.sup.7 = H III. 376 " " " R.sup.4     = H " " "     R.sup.7 = CH.sub.3 III. 377 " " " R.sup.4 = CH.sub.3 " " "         R.sup.7 = H III. 378 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 =     CH.sub.3 III. 379 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " "     R.sup.7 = H      III. 380 " " " R.sup.4  =H " " "     R.sup.7 = CH.sub.3 III. 381 " " "     R.sup.4 = CH.sub.3 " " "     R.sup.7 = H III. 382 " " " R.sup.4 =     CH.sub.3 " " "     R.sup.7 = CH.sub.3 III. 383 " " C.sub.8 H.sub.17 (n)     R.sup.4 = H " " "     R.sup.7 = H III. 384 " " " R.sup.4 = H " " "     R.sup.7 = CH.sub.3 III. 385 " " " R.sup.4 = CH.sub.3 " " "     R.sup.7 = H      III. 386 " " " R.sup. 4 = CH.sub.3 " " "     R.sup.7 = CH.sub.3  III.     387      ##STR79##      " H R.sup.4 =      H " "     ##STR80##       III. 388 " " " R.sup.4 = CH.sub.3 " " " III. 389 " " CH.sub.3 R.sup.4     = H " " " III. 390 " " " R.sup.4 = CH.sub.3 " " " III. 391 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 392 " " " R.sup.4 = CH.sub.3 " " " III.     393 " " C.sub. 2 H.sub.4 OH R.sup.4 = H " " " III. 394 " " " R.sup.4 =     CH.sub.3 " " " III. 395 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     396 " " " R.sup.4 = CH.sub.3 " " "  III. 397 " " H R.sup.4 = H " "      ##STR81##       III. 398 " " " R.sup.4 = CH.sub.3 " " " III. 399 " " CH.sub.3 R.sup.4     = H " " " III. 400 " " " R.sup.4 = CH.sub.3 " " " III. 401 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 402 " " " R.sup.4 = CH.sub.3 " " " III.     403 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 404 " " " R.sup.4 =     CH.sub.3 " " " III. 405 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     406 " " " R.sup.4 = CH.sub.3 " " "  III. 407 " " H R.sup.4 = H " "      ##STR82##       III. 408 " " " R.sup.4 =  CH.sub.3 " " " III. 409 " " CH.sub.3 R.sup.4     = H " " " III. 410 " " " R.sup.4 = CH.sub.3 " " " III. 411 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 412 " " " R.sup.4 = CH.sub.3 " " " III.     413 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 414 " " " R.sup.4 =     CH.sub.3 " " " III. 415 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     416 " " " R.sup.4 = CH.sub.3 " " "  III. 417 " "  H R.sup.4 = H " "      ##STR83##       III. 418 " " " R.sup.4 = CH.sub.3 " " " III. 419 " " CH.sub.3 R.sup.4     = H " " " III. 420 " " " R.sup.4 = CH.sub.3 " " " III. 421 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 422 " " " R.sup.4 = CH.sub.3 " " " III.     423 " " C.sub.2 H.sub.4 OH R.sup.4 =  " " " III. 424 " " " R.sup.4 =     CH.sub.3 " " "  III. 425 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " "     III. 426 " " " R.sup.4 = CH.sub.3 " " "      III. 427     ##STR84##      " H R.sup.4 =      H " "     ##STR85##       III. 428 " " " R.sup.4 = CH.sub.3 " " " III. 429 " " CH.sub.3 R.sup.4     = H " " " III. 430 " " " R.sup.4 = CH.sub.3 " " " III. 431 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 432 " " " R.sup.4 CH.sub.3 " " " III. 433     " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 434 " " " R.sup.4 =     CH.sub.3 " " " III. 435 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     436 " " " R.sup.4 = CH.sub.3 " " "  III. 437 " " H R.sup.4 = H " "      ##STR86##       III. 438 " " " R.sup.4 = CH.sub.3 " " " III. 439 " " CH.sub.3 R.sup.4     =  H " " " III. 440 " " " R.sup.4 = CH.sub.3 " " " III. 441 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 442 " " " R.sup.4 = CH.sub.3 " " " III.     443 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 444 " " " R.sup.4 =     CH.sub.3 " " " III. 445 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     446 " " " R.sup.4 = CH.sub.3 " " "  III. 447 " " H R.sup.4 = H " "      ##STR87##       III. 448 " " " R.sup.4 = CH.sub.3 " " " III. 449 " " CH.sub.3 R.sup.4     = H " " " III. 450 " " " R.sup.4 = CH.sub.3 " " " III. 451 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 452 " " " R.sup.4 = CH.sub.3 " " " III.     453 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 454 " " " R.sup.4 =     CH.sub.3 " " " III. 455 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " "  "     III. 456 " " " R.sup.4 = CH.sub.3 " " "  III. 457 " " H R.sup.4 = H " "      ##STR88##       III. 458 " " " R.sup.4 = CH.sub.3 " " " III. 459 " " CH.sub.3 R.sup.4     = H " " " III. 460 " " " R.sup.4 = CH.sub.3 " " " III. 461 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 462 " " " R.sup.4 = CH.sub.3 " " " III.     463 " " C.sub.2 H.sub.4 OH R.sup.4  = H " " " III. 464 " " " R.sup.4 =     CH.sub.3 " " " III. 465 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     466 " " " R.sup.4 = CH.sub.3 " " "      III. 467     ##STR89##      ##STR90##      H R.sup.4 =      H " "     ##STR91##       III. 468 " " " R.sup.4 = CH.sub.3 " " " III. 469 " " CH.sub.3 R.sup.4     = H " " " III. 470 " "  " R.sup.4 = CH.sub.3 " " " III. 471 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 472 " " " R.sup.4 = CH.sub.3 " " " III.     473 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 474 " " " R.sup.4 =     CH.sub.3 " " "  III. 475 " " H R.sup.4 =      H " "     ##STR92##       III. 476 " " " R.sup.4 = CH.sub.3 " " " III. 477 " " CH.sub.3 R.sup.4     = H " " " III. 478 " " " R.sup.4 = CH.sub.3 " " " III. 479 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 480 " " " R.sup.4 = CH.sub.3 " " " III.     481 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 482 " " " R.sup.4 =     CH.sub.3 " " "  III. 483 " " H R.sup.4 =      H " "     ##STR93##       III. 484 " " " R.sup.4 = CH.sub.3 " " " III. 485 " " CH.sub.3 R.sup.4     =  H " " " III. 486 " " " R.sup.4 = CH.sub.3 " " " III. 487 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 488 " " " R.sup.4 = CH.sub.3 " " " III.     489 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 490 " " " R.sup.4 =     CH.sub.3 " " "  III. 491 " " H R.sup.4 =      H " "     ##STR94##       III. 492 " " " R.sup.4 = CH.sub.3 " " " III. 493 " "  CH.sub.3 R.sup.4     = H " " " III. 494 " " " R.sup.4 = CH.sub.3 " " " III. 495 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 496 " " " R.sup.4 = CH.sub.3 " " " III.     497 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 498 " " " R.sup.4 =     CH.sub.3 " " "      III. 499 "     ##STR95##      H R.sup.4 =      H " "     ##STR96##        III. 500 " " " R.sup.4 = CH.sub.3 " " "  III. 501 " " " R.sup.4 = H "     "      ##STR97##       III. 502 " " " R.sup.4 = CH.sub.3 " " "  III. 503 " " " R.sup.4 = H "     "      ##STR98##       III. 504 " " " R.sup.4 = CH.sub.3 " " "  III. 505 " " " R.sup.4 = H "     "      ##STR99##       III. 506 " " " R.sup.4 = CH.sub.3 " " "      III. 507 "     ##STR100##      " R.sup.4 =      H " "     ##STR101##       III. 508 " " " R.sup.4 = CH.sub.3 " " " III. 509 " " CH.sub.3 R.sup.4     = H " " " III. 510 " " " R.sup.4 = CH.sub.3 " " " III. 511 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 512 " " " R.sup.4 =  CH.sub.3 " " " III.     513 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 514 " " " R.sup.4 =     CH.sub.3 " " "  III. 515 " " H R.sup.4 =      H " "     ##STR102##       III. 516 " " " R.sup.4 = CH.sub.3 " " " III. 517 " " CH.sub.3 R.sup.4     = H " " " III. 518 " " " R.sup.4 = CH.sub.3 " " " III. 519 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 520 " " "  R.sup.4 = CH.sub.3 " " " III.     521 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 522 " " " R.sup.4 =     CH.sub.3 " " "  III. 523 " " H R.sup.4 =      H " "     ##STR103##       III. 524 " " " R.sup.4 = CH.sub.3 " " " III. 525 " " CH.sub.3 R.sup.4     = H " " "  III. 526 " " " R.sup.4 =      CH.sub.3 " "     ##STR104##       III. 527 " " C.sub.2 H.sub.5 R.sup.4 =      H " "     ##STR105##       III. 528 " " " R.sup.4 = CH.sub.3 " " " III. 529 " " C.sub.8 H.sub.17     (n) R.sup.4 = H " " " III. 530 " " " R.sup.4 = CH.sub.3 " " "  III. 531     " " H R.sup.4 =      H " "     ##STR106##       III. 532 " " " R.sup.4 = CH.sub.3 " " " III. 533 " " CH.sub. 3 R.sup.4     = H " " " III. 534 " " " R.sup.4 = CH.sub.3 " " " III. 535 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 536 " " " R.sup.4 = CH.sub.3 " " " III.     537 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 538 " " " R.sup.4 =     CH.sub.3 " " "       III. 539 "     ##STR107##      H R.sup.4 =      H " H     ##STR108##       III. 540 " "  " R.sup.4 = CH.sub.3 " " " III. 541 " " CH.sub.3 R.sup.4     = H " " " III. 542 " " " R.sup.4 = CH.sub.3 " " " III. 543 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 544 " " " R.sup.4 = CH.sub.3 " " " III.     545 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 546 " " " R.sup.4 =     CH.sub.3 " " " III. 547 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     548 " " " R.sup.4 = CH.sub.3 " " "  III. 549 " " H R.sup.4 = H " "      ##STR109##       III. 550 " " " R.sup.4 = CH.sub.3 " " " III. 551 " " CH.sub.3 R.sup.4     = H " " " III. 552 " " " R.sup.4 = CH.sub.3 " " " III. 553 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 554 " " " R.sup.4 = CH.sub.3 " " " III.     555 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 556 " " " R.sup.4 =     CH.sub. 3 " " " III. 556a " " " R.sup.4 = CH.sub.3 " " " III. 557 " "     C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III. 558 " " " R.sup.4 =     CH.sub.3 " " "  III. 559 " " H R.sup.4 =      H " "     ##STR110##       III. 560 " " " R.sup.4 = CH.sub.3 " " " III. 561 " " CH.sub.3 R.sup.4     = H " " " III. 562 " " " R.sup.4 = CH.sub.3 " " " III. 563 " " C.sub.2     H.sub. 5 R.sup.4 = H " " " III. 564 " " " R.sup.4 = CH.sub.3 " " " III.     565 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 566 " " " R.sup.4 =     CH.sub.3 " " " III. 567 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     568 " " " R.sup.4 = CH.sub.3 " " "  III. 569 " " H R.sup.4 = H " "      ##STR111##       III. 570 " " " R.sup.4 = CH.sub.3 " " " III. 571 " " CH.sub.3 R.sup.4     = H " " " III. 572 " " " R.sup.4 = CH.sub.3 " " " III. 573 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 574 " " " R.sup.4 = CH.sub.3 " " " III.     575 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 576 " " " R.sup.4 =     CH.sub.3 " " " III. 577 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     578 " " " R.sup.4 = CH.sub.3 " " "      III. 579 "     ##STR112##      H R.sup.4 =      H " "     ##STR113##       III. 580 " " " R.sup.4 = CH.sub.3 " " " III. 581 " " CH.sub.3 R.sup.4     = H " " " III. 582 " " " R.sup.4 = CH.sub.3 " " " III. 583 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 584 " " " R.sup.4 = CH.sub.3 " " " III.     585 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 586 " " " R.sup.4 =      CH.sub.3 " " " III. 587 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " "     III. 588 " " " R.sup.4 = CH.sub.3 " " "  III. 589 " " H R.sup.4 = H " "      ##STR114##       III. 590 " " " R.sup.4 = CH.sub.3 " " " III. 591 " " CH.sub.3 R.sup.4     = H " " " III. 592 " " " R.sup.4 = CH.sub.3 " " " III. 593 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 594 " " "  R.sup.4 = CH.sub.3 " " " III.     595 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 596 " " " R.sup.4 =     CH.sub.3 " " " III. 597 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     598 " " " R.sup.4 = CH.sub.3 " " "  III. 599 " " H R.sup.4 = H " "      ##STR115##       III. 600 " " " R.sup.4 =      CH.sub.3 " "     ##STR116##        III. 601 " " CH.sub.3 R.sup.4 =      H " "     ##STR117##       III. 602 " " " R.sup.4 = CH.sub.3 " " " III. 603 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 604 " " " R.sup.4 = CH.sub.3 " " " III. 605 " "     C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 606 " " " R.sup.4 = CH.sub.3 "     " " III. 607 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III. 608 " " "     R.sup.4 = CH.sub.3 " " "  III. 609 " " H R.sup.4 =      H " "     ##STR118##       III. 610 " " " R.sup.4 = CH.sub.3 " " " III. 611 " " CH.sub.3 R.sup.4     = H " " " III. 612 " " " R.sup.4 = CH.sub.3 " " " III. 613 " " C.sub.2     H.sub.5 R.sup.4 = H  " " " III. 614 " " " R.sup.4 = CH.sub.3 " " " III.     615 " " C.sub.2 H.sub.4 OH R.sup.4 = H " " " III. 616 " " " R.sup.4 =     CH.sub.3 " " " III. 617 " " C.sub.12 H.sub.25 (n) R.sup.4 = H " " " III.     618 " " " R.sup.4 = CH.sub.3 " " "      III. 619 "     ##STR119##      H R.sup.4 =      H " "     ##STR120##       III. 620 " " " R.sup.4 = CH.sub.3 " " " III. 621 " " CH.sub.3 R.sup.4     = H " " " III. 622 " " " R.sup.4 = CH.sub.3 " " " III. 623 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 624 " " " R.sup.4 = CH.sub.3 " " " III.     625 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 626 " " " R.sup.4 =     CH.sub.3 " " "  III. 627 " " H R.sup.4 =      H " "     ##STR121##       III. 628 " " " R.sup.4 = CH.sub.3 " " " III. 629 " " CH.sub.3 R.sup.4     = H " " " III. 630 " " " R.sup.4 = CH.sub.3 " " " III. 631 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 632 " " " R.sup.4 = CH.sub.3 " " " III.     633 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 634 " " " R.sup.4 =     CH.sub.3 " " "  III. 635 " " H R.sup.4 =      H " "     ##STR122##       III. 636a " " " R.sup.4 =      CH.sub.3 " "     ##STR123##       III. 636 " "  " R.sup.4 =      CH.sub.3 " "     ##STR124##       III. 637 " " CH.sub.3 R.sup.4 = H " " " III. 638 " " " R.sup.4 =     CH.sub.3 " " " III. 639 " " C.sub.2 H.sub.5 R.sup.4 = H " " " III. 640 "     " " R.sup.4 = CH.sub.3 " " " III. 641 " " C.sub.8 H.sub.17 (n) R.sup.4 = H      " " " III. 642 " " " R.sup.4 = CH.sub.3 " " "  III. 643 " " H R.sup.4 = H      " "      ##STR125##       III. 644 " " " R.sup.4 = CH.sub.3 " " " III. 645 " " CH.sub.3 R.sup.4     = H " " " III. 646 " " " R.sup.4 = CH.sub.3 " " " III. 647 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 648 " " " R.sup.4 = CH.sub.3 " " " III.     649 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 650 " " " R.sup.4 =     CH.sub.3 " " "      III. 651 "     ##STR126##      CH.sub.3 R.sup.4 =      H " "     ##STR127##       III. 652 " " " R.sup.4 = CH.sub.3 " " " III. 653 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 654 " " " R.sup.4 = CH.sub.3 " " "  III. 655 " "     CH.sub.3 R.sup.4 =      H " "     ##STR128##       III. 656 " " " R.sup.4 = CH.sub.3 " " " III. 657 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 658 " " " R.sup.4 = CH.sub.3 " " "  III. 659 " "     CH.sub.3 R.sup.4 =      H " "     ##STR129##       III. 660 " " " R.sup.4 = CH.sub.3 " " " III. 661 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 662 " " " R.sup.4 = CH.sub.3 " " "  III. 663 " "     CH.sub.3 R.sup.4 =      H " "     ##STR130##       III. 664 " " " R.sup.4 = CH.sub.3 " " " III. 665 " " C.sub.2 H.sub.5     R.sup.4 = H " " " III. 666 " " " R.sup.4 = CH.sub.3 " " "  III. 667 "      ##STR131##      H R.sup.4 =      H " "     ##STR132##       II. 668 " " " R.sup.4 = CH.sub.3 " " " III. 669 " " CH.sub.3 R.sup.4 = H      " " " III. 670 " " " R.sup.4 = CH.sub.3 " " " III. 671 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 672 " " " R.sup.4 = CH.sub.3 " " " III.     673 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 674 " " " R.sup.4 =     CH.sub.3 " " "  III. 675 " " H R.sup.4 =      H " "     ##STR133##       III. 676 " " " R.sup.4 = CH.sub.3 " " " III. 677 " " CH.sub.3 R.sup.4     = H " " " III. 678 " " " R.sup.4 = CH.sub.3 " " " III. 679 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 680 " " " R.sup.4 = CH.sub.3 " " " III.     681 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 682 " " " R.sup.4 =     CH.sub.3 " " "  III. 683 " " H R.sup.4 =      H " "     ##STR134##       III. 684 " " " R.sup.4 =      CH.sub.3 " "     ##STR135##       III. 685 " " CH.sub.3 R.sup.4 = H " " "  III. 686 " " " R.sup.4 =     CH.sub.3 " " " III. 687 " " C.sub.2 H.sub.5 R.sup.4 = H " " " III. 688 "     " " R.sup.4 = CH.sub.3 " " " III. 689 " " C.sub.8 H.sub.17 (n) R.sup.4 = H      " " " III. 690 " " " R.sup.4 = CH.sub.3 " " "  III. 691 " " H R.sup.4 = H      " "      ##STR136##       III. 692 " " " R.sup.4 = CH.sub.3 " " " III. 693 " " CH.sub.3 R.sup.4     = H " " " III. 694 " " " R.sup.4 = CH.sub.3 " " " III. 695 " " C.sub.2     H.sub.5 R.sup.4 = H " " " III. 696 " " " R.sup.4 = CH.sub.3 " " " III.     697 " " C.sub.8 H.sub.17 (n) R.sup.4 = H " " " III. 698 " " " R.sup.4 =     CH.sub.3 " " "      III. 699 "     ##STR137##       R.sup.4 =      H "  "     ##STR138##       III. 700 " "  R.sup.4 = CH.sub.3 " " "  III. 701 " "  R.sup.4 = H " "      ##STR139##       III. 702 " "  R.sup.4 = CH.sub.3 " " "  III. 703 " "  R.sup.4 = H " "      ##STR140##       III. 704 " "  R.sup.4 = CH.sub.3 " " "  III. 705 " "  R.sup.4  = H " "      ##STR141##       III. 706 " "  R.sup.4 = CH.sub.3 " " "      III. 707 "     ##STR142##       R.sup.4 =      H " "     ##STR143##       III. 708 " "  R.sup.4 = CH.sub.3 " " "  III. 709 " "  R.sup.4 = H " "      ##STR144##       III. 710 " "  R.sup.4 = CH.sub.3 " " "  III. 711 " "  R.sup.4 = H " "      ##STR145##       III. 712 " "  R.sup.4 = CH.sub.3 " " "  III. 713 " "  R.sup.4 = H " "      ##STR146##       III. 714 " "  R.sup.4 = CH.sub.3 " " "      III. 715 "     ##STR147##      H R.sup.4 =      H " CN     ##STR148##      III. 716     ##STR149##      ##STR150##      " R.sup.7 = CH.sub.3R.sup.8 =      CH.sub.3 " "     ##STR151##       III. 717 "     ##STR152##      " R.sup.7 = HR.sup.3 = C.sub.2      H.sub.5 " "     ##STR153##      III. 718     ##STR154##      ##STR155##      " R.sup.8 = H " " "  III. 719 " " " R.sup.8 = CH.sub.3 " " "  III. 720     "      ##STR156##      " R.sup.3 = C.sub.2 H.sub.5 " " "       III. 721     ##STR157##      ##STR158##      " R.sup.7 =      H " "     ##STR159##      III. 722     ##STR160##      " " R.sup.4 = H " " "      III. 723     ##STR161##      ##STR162##      C.sub.2 H.sub.5 R.sup.4 =      CH.sub.3 " H     ##STR163##      III. 724     ##STR164##      ##STR165##      CH.sub.3 R.sup.11 = CH.sub.3 " " "      III. 725 "     ##STR166##      H -- " CN      ##STR167##      III. 726 " " " --     ##STR168##      III. 727     ##STR169##      " "  " "      ##STR170##      III. 728 " " "  " "     ##STR171##      III. 729 " " "  " "     ##STR172##      III. 730     ##STR173##      ##STR174##      "  " "      ##STR175##      III. 731     ##STR176##      ##STR177##      "  " " "      III. 732 " " "  CN CN     ##STR178##      III. 733 " " "  " "     ##STR179##

The novel dyes (I) are prepared by condensing methylene compounds of theformula (IV) ##STR180## with C-3, C-5, C-7, C-9 or C-11 units under acidor alkaline conditions in the presence of a solvent at 20° C.-120° C.Possible C-3, C-5, C-7, C-9 and C-11 units are for example:

C-3: 1,1,3,3-tetramethoxypropane, 2-cyanomalonaldehyde,2-fluoromalonaldehyde, 2-chloromalonaldehyde, 2-bromomalonaldehyde and##STR181##

In the formulae, X.sup.⊖ is one equivalent of an anion, for exampleCl.sup.⊖, 1/2 ZnCl₄ 2-, Br.sup.⊖, I.sup.⊖, tosylate, benzenesulfonate,trifluoroacetate, tetrafluoroborate and perchlorate.

Y² has the abovementioned meanings.

Suitable solvents for the reactions are for example dimethylformamide,N-methylpyrrolidone, dimethoxyethane, ethylene glycol monomethyl etheror mixtures thereof.

The invention also relates to a process for preparing symmetricalheptamethines of the formula ##STR182## in which D, Y¹ and Y² have theabovementioned meanings, by reacting methylene compounds of the formula##STR183## with pyridinium salts of the formula ##STR184## where Y² hasthe abovementioned meanings, X.sup.⊖ is one equivalent of an anion andR¹¹ is C₁ -C₈ -alkyl or C₇ -C₁₀ -aralkyl.

The reaction of methylene compounds of the formula (IV) with1,1,3,3-tetramethoxypropanes which are substituted in the 2-position byY² gives under suitable reaction conditions 1:1 products, salts of theformula (VI) ##STR185## These can be reacted directly or, if desired,after intermediate isolation or after ring opening to the aldehydes ofthe formula (VII): ##STR186## with methylene compounds of the formula(IV) to give symmetrical or asymmetrical pentamethines of the formula(VIIIa) or with cycloammonium compounds to give pentamethines of theformula (VIIa). ##STR187##

Suitable cycloammonium compounds are for example: ##STR188## where R andX.sup.⊖ have the abovementioned meanings, although X.sup.⊖ can also beH₃ CSO₄ ⊖ and C₂ H₅ SO₄ ⊖.

The reaction of alkyl cyanide with 2 moles of (VI) or (VII) leads toundecamethines of the formula (X) ##STR189## The aldehydes of theformula (VII) can be converted by reaction with dicarboxylic acids orfunctional derivatives thereof into polymethines of the formula (IX). Inthe formula (IX), D, Y² and Y¹ have the abovementioned meanings##STR190## and p is 0, 1, 2 or 3. In this process the radicals D arepreferably identical. In this way it is possible to obtain nonamethines(p=0) from malonic acid, undecamethines (p=1) from glutaconic acid andtridecamethines (p=2) from piperylenedicarboxylic acid.

Starting from the salts (VI) or the corresponding aldehydes (VII), thelonger-chain methines, in particular those which are substituted in thechain, are accessible by the following pathways: ##STR191##

In the formulae (XI) to (XV),

Y¹ is preferably --CN,

Y² is preferably chlorine, phenyl, pyridyl, --CN, hydrogen or togetherwith a further Y² a five- or six-membered ring which may have a fused-onbenzene ring,

q is 0, 1, 2 or 3, and

Z is C₁ -C₄ -alkyl. ##STR192##

In the formulae (XVIII) to (XXI), Y¹ is preferably --CN, Y² ispreferably hydrogen, --CN, chlorine, phenyl, pyridyl or together with afurther Y² a five- or six-membered ring which may have a fused-onbenzene ring and p is 0, 1, 2 or 3.

The new methine dyes (I) can be converted in a conventional manner byprotonation or alkylation into cationic methine dyes of the formula(XVI). The radicals R, which have the abovementioned meanings, can beidentical or different. ##STR193##

Suitable alkylating agents are for example: dimethyl sulfate, diethylsulfate, trimethyloxonium tetrafluoroborate, triethyloxoniumtetrafluoroborate, methyl, ethyl, n-propyl, n-butyl, iso-butyl,sec.-butyl, n-pentyl, 3-methylbutyl, n-hexyl, n-heptyl, n-octyl,2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl,n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl,n-nonadecyl, n-eicosanyl chloride, bromide or iodide, and methyl, ethyl,n-propyl, n-butyl, sec.-butyl, iso-butyl, n-pentyl, 3-methylbutyl,n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl,n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl,n-heptadecyl, n-octadecyl, n-nonadecyl and n-eicosanyl benzene- orp-toluene-sulfonate.

X.sup.⊖ is one equivalent of an anion and, in addition to the meaningsalready mentioned for X.sup.⊖, can also have the meaning H₃ CSO₄ ⊖ andH₅ C₂ SO₄ ⊖.

Examples of the dyes are the dyes of the formula (XVI) mentioned inTable 2:

                  TABLE 2                                                         ______________________________________                                        Dye No. from Table 1                                                                        the one R   the other R                                         ______________________________________                                        III. 1        H           H                                                   III. 2        C.sub.2 H.sub.5                                                                           C.sub.8 H.sub.17 (n)                                III. 4        C.sub.12 H.sub.25 (n)                                                                     C.sub.12 H.sub.25 (n)                               III. 5        H           H                                                   III. 7        n-C.sub.4 H.sub.9                                                                         n-C.sub.4 H.sub.9                                   III. 8        C.sub.12 H.sub.25 (n)                                                                     C.sub.20 H.sub.21 (n)                               III. 9        H           H                                                   III. 11       n-C.sub.4 H.sub.9                                                                         C.sub.10 H.sub.21 (n)                               III. 14       C.sub.2 H.sub.5                                                                           H                                                   III. 14       C.sub.2 H.sub.5                                                                           C.sub.12 H.sub.25 (n)                               III. 17       H           H                                                   III. 19       C.sub.2 H.sub.5                                                                           H                                                   III. 24       C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 34       C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 34       C.sub.2 H.sub.5                                                                           C.sub.8 H.sub.17 (n)                                III. 40       n-C.sub.4 H.sub.9                                                                         n-C.sub.4 H.sub.9                                   III. 47       C.sub.2 H.sub.5                                                                           C.sub. 2 H.sub.5                                    III. 48       C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 58       C.sub.2 H.sub.5                                                                           C.sub.5 H.sub.11 (n)                                III. 63       n-C.sub.4 H.sub.9                                                                         C.sub.10 H.sub.21 (n)                               III. 65       H           H                                                   III. 66       H           H                                                   III. 67       H           H                                                   III. 68       H           H                                                   III. 69       H           H                                                   III. 71       H           H                                                   III. 74       H           H                                                   III. 76       H           C.sub.12 H.sub.25 (n)                               III. 77       H           H                                                   III. 78       C.sub.2 H.sub.5                                                                           H                                                   III. 81       H           H                                                   III. 82       C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 83       H           H                                                   III. 85       H           H                                                   III. 87       H           H                                                   III. 87       C.sub.8 H.sub.17 (n)                                                                      C.sub.8 H.sub.17 (n)                                III. 88       H           H                                                   III. 89       CH.sub.3    CH.sub.3                                            III. 91       C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 97       C.sub.12 H.sub.25 (n)                                                                     C.sub.12 H.sub.25 (n)                               III. 98       H           H                                                   III. 100      C.sub.2 H.sub.5                                                                           C.sub.9 H.sub.19 (n)                                III. 103      H           H                                                   III. 105      C.sub.2 H.sub.5                                                                            ##STR194##                                         III. 108      H           H                                                   III. 110      C.sub.2 H.sub.5                                                                           C.sub.16 H.sub.35 (n)                               III. 118      H           H                                                   III. 119      CH.sub.3    C.sub.8 H.sub.17 (n)                                III. 125      C.sub.2 H.sub.5                                                                           C.sub.10 H.sub.21 (n)                               III. 128      H           H                                                   III. 132      C.sub.2 H.sub.5                                                                           H                                                   III. 132      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 135      H           H                                                   III. 136      C.sub.12 H.sub.25 (n)                                                                     C.sub.12 H.sub.25 (n)                               III. 138      H           H                                                   III. 139      H           H                                                   III. 142      H           H                                                   III. 144      H           H                                                   III. 146      H           H                                                   III. 147      H           H                                                   III. 150      H           H                                                   III. 154      H           H                                                   III. 156      CH.sub.3    C.sub. 12 H.sub.25 (n)                              III. 158      C.sub.2 H.sub.5                                                                           C.sub.10 H.sub.21 (n)                               III. 160      H           H -III. 162 C.sub.2 H.sub.5 C.sub.2 H.sub.5         III. 164      n-C.sub.4 H.sub.9                                                                         C.sub.8 H.sub.17 (n)                                III. 166      C.sub.12 H.sub.25 (n)                                                                     C.sub.12 H.sub.25 (n)                               III. 168      H           H                                                   III. 169      H           H                                                   III. 170      C.sub.2 H.sub.5                                                                           C.sub.10 H.sub.21 (n)                               III. 174      C.sub.12 H.sub.25 (n)                                                                     C.sub.12 H.sub.25 (n)                               III. 176      H           H                                                   III. 178      C.sub.2 H.sub.5                                                                           C.sub.20 H.sub.41 (n)                               III. 184      H           H                                                   III. 186      C.sub.2 H.sub.5                                                                           C.sub.10 H.sub.21 (n)                               III. 192      H           H                                                   III. 194      H           H                                                   III. 195      H           H                                                   III. 198      C.sub.2 H.sub.5                                                                           H                                                   III. 200      C.sub.2 H.sub.5                                                                           H                                                   III. 200      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 202      C.sub.2 H.sub.5                                                                           C.sub.8 H.sub.17 (n)                                III. 210      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 216      H           H                                                   III. 222      C.sub.2 H.sub.5                                                                           H                                                   III. 224      C.sub.2 H.sub.5                                                                           H                                                   III. 226      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 236      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 240      H           H                                                   III. 245      H           H                                                   III. 250      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 256      n-C.sub.4 H.sub.9                                                                         n-C.sub.4 H.sub.9                                   III. 264      H           H                                                   III. 268      H           H                                                   III. 270      C.sub.2 H.sub.5                                                                           H                                                   III. 274      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 282      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 284      C.sub.8 H.sub.17 (n)                                                                      C.sub.2 H.sub.5                                     III. 288      H           H                                                   III. 290      H           H                                                   III. 291      H           H                                                   III. 294      CH.sub.3    C.sub.20 H.sub.41 (n)                               III. 297      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 302      C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 307      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 311      H           H                                                   III. 315      CH.sub.3    C.sub.2 H.sub.5                                     III. 319      C.sub.2 H.sub.5                                                                           C.sub.5 H.sub.11 (n)                                III. 324      C.sub.8 H.sub.17 (n)                                                                      C.sub.8 H.sub.17 (n)                                III. 326      C.sub.8 H.sub.17 (n)                                                                      n-C.sub.4 H.sub.9                                   III. 328      H           H                                                   III. 331      H           H                                                   III. 335      CH.sub.3    C.sub.2 H.sub.5                                     III. 340      C.sub.2 H.sub.4 OH                                                                        H                                                   III. 346      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 353      CH.sub.3    CH.sub.3                                            III. 357      C.sub.2 H.sub.5                                                                           n-C.sub.4 H.sub.9                                   III. 363      C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 367      C.sub.8 H.sub.17 (n)                                                                      n-C.sub.4 H.sub.9                                   III. 368      H           H                                                   III. 371      H           H                                                   III. 377      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 382      C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 388      H           H                                                   III. 395      C.sub.12 H.sub.25 (n)                                                                     C.sub.6 H.sub.13 (n)                                III. 402      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 407      H           H                                                   III. 408      H           H                                                   III. 412      C.sub.2 H.sub.5                                                                           n-C.sub.4 H.sub.9                                   III. 416      C.sub.12 H.sub.25 (n)                                                                     H                                                   III. 423      C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 427      H           H                                                   III. 430      CH.sub.3    CH.sub.3                                            III. 435      C.sub.12 H.sub.25 (n)                                                                     H                                                   III. 441      C.sub.2 H.sub.5                                                                           n-C.sub.4 H.sub.9                                   III. 448      H           H                                                   III. 454      C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 458      H           H                                                   III. 462      C.sub.2 H.sub.5                                                                           n-C.sub.4 H.sub.9                                   III. 467      H           H                                                   III. 468      H           H                                                   III. 472      C.sub.2 H.sub.5                                                                           n-C.sub.4 H.sub.9                                   III. 478      CH.sub.3                                                                                   ##STR195##                                         III. 480      C.sub.2 H.sub.5                                                                           H                                                   III. 485      CH.sub.3    H                                                   III. 489      C.sub.8 H.sub.17 (n)                                                                      C.sub.8 H.sub.17 (n)                                III. 491      H           H                                                   III. 495      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 498      C.sub.8 H.sub.17 (n)                                                                      n-C.sub.4 H.sub.9                                   III. 499      H           H                                                   III. 503      H           H                                                   III. 507      H           H                                                   III. 512      C.sub.2 H.sub.5                                                                           CH.sub.3                                            III. 515      H           H                                                   III. 520      C.sub.2 H.sub.5                                                                           H                                                   III. 521      C.sub.8 H.sub.17 (n)                                                                      C.sub.8 H.sub.17 (n)                                III. 526      CH.sub.3    n-C.sub.4 H.sub.9                                   III. 530      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 531      H           H                                                   III. 535      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 539      H           H                                                   III. 542      CH.sub.3    CH.sub.3                                            III. 543      C.sub.2 H.sub.5                                                                           H                                                   III. 545      C.sub.2 H.sub.4 OH                                                                        H                                                   III. 547      C.sub.12 H.sub.25 (n)                                                                     H                                                   III. 549      H           H                                                   III. 550      H           H                                                   III. 556      C.sub.2 H.sub.4 OH                                                                        C.sub.2 H.sub.5                                     III. 557      C.sub.12 H.sub.25 (n)                                                                     C.sub.12 H.sub.25 (n)                               III. 559      H           H                                                   III. 560      H           H                                                   III. 567      C.sub.12 H.sub.25 (n)                                                                     H                                                   III. 569      H           H                                                   III. 572      CH.sub.3    C.sub.2 H.sub.5                                     III. 573      C.sub.2 H.sub.5                                                                           C.sub.10 H.sub.21 (n)                               III. 579      H           H                                                   III. 583      C.sub.2 H.sub.5                                                                           H                                                   III. 584      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 589      H           H                                                   III. 593      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 598      C.sub.12 H.sub.25 (n)                                                                     H                                                   III. 599      H           H                                                   III. 601      CH.sub.3    C.sub.12 H.sub.25 (n)                               III. 604      C.sub.2 H.sub.5                                                                           H                                                   III. 609      H           H                                                   III. 612      CH.sub.3    n-C.sub.4 H.sub.9                                   III. 617      C.sub.12 H.sub.25 (n)                                                                     H                                                   III. 619      H           H                                                   III. 621      CH.sub.3    H                                                   III. 623      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 627      H           H                                                   III. 628      H           H                                                   III. 633      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 635      H           H                                                   III. 639      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 641      C.sub.8 H.sub.17 (n)                                                                      C.sub.8 H.sub.17 (n)                                III. 643      H           H                                                   III. 645      CH.sub.3    C.sub.2 H.sub.5                                     III. 649      C.sub.8 H.sub.17 (n)                                                                      H                                                   III. 651      CH.sub.3    H                                                   III. 654      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 658      C.sub.2 H.sub.5                                                                           n-C.sub.4 H.sub.9                                   III. 664      CH.sub.3    H                                                   III. 667      H           H                                                   III. 670      CH.sub.3    CH.sub.3                                            III. 671      C.sub.2 H.sub.5                                                                           C.sub.10 H.sub.21 (n)                               III. 680      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 682      C.sub.8 H.sub.17 (n)                                                                      C.sub.8 H.sub.17 (n)                                III. 689      C.sub.8 H.sub.17 (n)                                                                      n-C.sub.4 H.sub.9                                   III. 695      C.sub. 2 H.sub.5                                                                          H                                                   III. 699      CH.sub.3    H                                                   III. 702      CH.sub.3    H                                                   III. 706      CH.sub.3    n-C.sub.4 H.sub.9                                   III. 707      H           H                                                   III. 711      CH.sub.3    C.sub.8 H.sub.17 (n)                                III. 715      H           H                                                   III. 716      H           H                                                   III. 717      H           H                                                   III. 718      H           H                                                   III. 719      H           H                                                   III. 720      H           H                                                   III. 720      C.sub.2 H.sub.5                                                                           H                                                   III. 721      C.sub.2 H.sub.5                                                                           H                                                   III. 721      H           H                                                   III. 722      H           H                                                   III. 722      C.sub.2 H.sub.5                                                                           H                                                   III. 722      C.sub.2 H.sub.5                                                                           H                                                   III. 723      H           C.sub.2 H.sub.5                                     III. 724      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 725      C.sub.8 H.sub.17                                                                          H                                                   III. 726      CH.sub.3    CH.sub.3                                            III. 727      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 728      H           H                                                   III. 729      C.sub.2 H.sub.5                                                                           C.sub.2 H.sub.5                                     III. 730      CH.sub.3    CH.sub.3                                            III. 731      H           H                                                   III. 732      C.sub.2 H.sub.5                                                                           H                                                   III. 733      CH.sub.3    CH.sub.3                                            ______________________________________                                    

The novel methine dyes of the formula (Ia) ##STR196## where D, Y¹, Y²and n have the abovementioned meaning and R is hydrogen, can beconverted in a conventional manner by deprotonation into anionic dyes ofthe formula (XVII) ##STR197## where D, Y¹, Y² and n have theabovementioned meanings and M.sup.⊕ is one equivalent of a cation.M.sup.⊕ is for example a lithium, sodium, potassium, cesium, calcium,ammonium, tetraphenylarsonium or tetraalkylammonium ion such astetramethyl-, tetraethyl-, tetrabutyl-, trimethylbenzyl-,triethylbenzyl- or trimethyldecyl-ammonium ion. The anions of theformula (XVII) are prepared by reacting the methine dyes of the formula(Ia) with bases such as alkali metal hydroxides, sodium alcoholates orpotassium tert.-butylate in a solvent at 0°-40° C. Suitable solvents arefor example: dimethylformamide and N-methylpyrrolidone.

The compounds of the formulae (XVI) and (XVII) likewise form part of thesubject-matter of the present invention.

The ##STR198## compounds required as starting materials and the C-3 andC-11 units are known or can be prepared in a conventional manner.

The processes for preparing the inventive compounds (I) from the salts(VI) or the aldehydes (VII) likewise form part of the subject-matter ofthe present invention.

Owing to their physical properties, such as the high absorption in thelongwave visible region up to the near infrared, the refractive index,the vaporizability under reduced pressure, the solubility in polymersolutions, the thermal and photochemical stability and/or the stablemorphology in thin films, the methine dyes (I) are suitable forpreparing optical recording media.

The invention also relates to optical recording media comprising a baseand a coat of a thermoplastic or crosslinked polymer which contains adye which is impervious to laser light, wherein the polymer contains atleast one methine dye as claimed in claim 1.

The recording systems according to the invention have a very highabsorption at the wavelengths of the lasers (for example He-Ne,Nd-glass, Nd-YAG, GaAs, GaAlAs and other suitable semiconductorinjection lasers) which are customarily used for recording information.Preference is given to those recording systems which have very highabsorption at the emission wavelength of semiconductor lasers from about750 to 1100 nm.

The polymer layers can be applied to an optically reflective layer insuch a way as to produce smooth absorption layers of optical qualitysuitable for inscribing the information to be stored with a highsignal-to-noise ratio.

The structure of recording media is known per se [J. Vac. Sci. Technol.18 (1) (Jan/Feb. 1981), 105].

A reflective layer can be present between the light-absorbent layer andthe base, so that the portion of the incident light which is notabsorbed in the colored layer is reflected at the reflector layer andpasses once more through the colored layer.

The incident light can also be received through a transparent substrate.A possible layer sequence is then: substrate, absorber and, if desired,reflector.

The reflective layer should be such that the light used for recordingand scanning is reflected quantitatively, if possible. Suitablereflective materials are, for example, aluminum, rhodium, gold, tin,lead, bismuth, copper and dielectric mirrors. The thickness of thereflective layer should be such that the light used for recording orscanning is reflected as completely as possible.

Mirrors having a low thermal conductivity are advantageous for thispurpose. The reflective (base) layer must have an optically smooth, flatsurface, and its surface must be such that the absorbent layer is firmlyadherent thereto. To obtain a favorable effect on the surface qualityand adhesion phenomena, the base and/or the reflector can be providedwith a smoothing coat of a thermoset or thermoplastic material.

Metallic reflective layers are preferably applied in a conventionalmanner by vapor deposition under reduced pressure or by affixingsuitable metal foils to the base. The laser-sensitive layer according tothe invention is preferably applied by whirler-coating on dissolved ordispersed dye in the presence of binders. Knife- or dip-coating arelikewise eligible methods for preparing the layers.

To apply the absorption layers from solution, a solution or, failingthat, a dispersion of the dye or dye mixture and the polymer is preparedin a suitable solvent, such as methylene chloride, chloroform, carbontetrachloride, acetone, methyl ethyl ketone, cyclohexanone, toluene,acetonitrile, ethyl acetate, methanol or mixtures thereof, and a binderis added, if desired.

The binder can be a radiation- or heat-curable resin, for example aphotopolymer, a silicone resin, an epoxy resin or a thermoplastic.

Preference is given to thermoplastics having no or only a very smallcrystalline domain and glass transition temperatures of above 35° C., inparticular above 75° C. Examples of suitable thermoplastics arewater-insoluble binders, such as (meth)acrylate polymers and copolymers,polystyrene homopolymers and copolymers, polyvinylcarbazole, polyvinylester copolymers, polyvinyl chloride, polyacrylonitrile and celluloseesters.

The dye formulation is then applied by knife- or dip-coating, butpreferably by whirler-coating, to a previously cleaned or pretreatedsubbing layer, and dried, or cured, in air. The film can also be driedor cured under reduced pressure, at elevated temperature or, ifappropriate, with radiation.

Depending on the structure of the system, the dye-in-polymer layer isapplied first, followed by the reflector, or vice versa. Interlayers andprotective layers or a reflective layer may be dispensed with. If thedye-in-polymer layer does not have adequate mechanical stability, it canbe coated with a transparent protective layer. Suitable for this purposeare a whole number of polymers which on application by whirler-coating,knife-coating or dip-coating from solution or by vapor deposition underreduced pressure, in particular in the case of fluorinated polymers, canform a protective layer.

If the (data storage) system is constructed from two identical ordifferent recording media in the form of a sandwich, a protective layercan be dispensed with. In addition to higher mechanical and rotodynamicstability, the sandwich structure offers the advantage of twice thestorage capacity.

Protective layers and/or interlayers are dispensable, given adequatequality of the optical recording medium. If interlayers cannot bedispensed with, their thickness must be chosen, having regard to therefractive index of the interlayer material and the laser lightwavelengths used, in such a way that no troublesome interference canarise.

The invention is illustrated in more detail by the examples below.

A 1. General method for preparing "PENTAMETHINES"

20 mmol of heteroarylacetonitrile, 20 mmol of1,1,3,3-tetramethoxypropane and 50 mEq of mineral acid (for examplehalohydric acid, perchloric acid, sulfuric acid or tetrafluoroboricacid) are gradually heated to the boil in 100 ml of ethylene glycolmonoethyl ether. The reaction mixture is maintained at that temperaturefor about 3 hours and is then gradually cooled down to room temperature,and the precipitated crystalline product is filtered off with suction.

Purification is effected by washing with mineral acid acetonitrile anddrying in a desiccator over KOH.

In place of tetramethoxypropane it is also possible to usetetramethoxypropanes which are substituted in the 2-position,malonaldehyde or C-substituted malonaldehydes or units of the formula##STR199##

A 2. General method for preparing "HEPTAMETHINES"

A 2.1

20 mmol of heteroarylacetonitrile, 10 mmol of Zincke-Aldehyd and 50 mEqof mineral acid are reacted in accordance with the pentamethine method(A 1).

A 2.2

20 mmol of heteroarylacetonitrile are dissolved with 2 g of finelyground potassium hydroxide in 50 ml of DMF. 10 mmol of Konig's salt areadded at room temperature. The mixture is stirred at room temperaturefor 3-5 h and poured onto 200 g of ice, 200 ml of water and 20 ml ofglacial acetic acid. The precipitate is filtered off with suction,washed with 1N acetic acid and recrystallized from an aceticacid/acetonitrile mixture.

A 2.3

2.2 is repeated, except that the Konig's salt is replaced by 10 mmol ofa pyridium salt.

A 2.4

2.2 is repeated, except that Konig's salt is replaced by 10 mmol ofcompound ##STR200##

A 3. General method for preparing "NONAMETHINES"

A 2.2 is repeated, except that the Konig's salt is replaced bydimethyl-(7-dimethylamino-2,4,6-heptatrienylidene)-ammoniumtetrachlorozincate. To work up, the reaction solution is poured onto 200g of ice and 20 ml of 47% strength HBr. The precipitate is filtered offwith suction and washed with 1N HBr.

A 4. General method for preparing "UNDECAMETHINES"

A 3. is repeated, except that the heptatrienylidene compound is replacedby dimethyl-(9-dimethylamino-2,4,6,8-nonatetraenylidene)ammoniumtetrachlorozincate.

A 5. General method for preparing pentamethines (VIII) and (VIIIa) fromsalts (VI)

A 5.1 Preparation of compounds of the formula (VIII)

20 mmol of acetonitrile derivative are dissolved with 2 g of finelyground potassium hydroxide in 50 ml of DMF. While cooling withice/water, 20 mmol of a salt of the formula (VI) are added a little at atime by spatula. The reaction mixture is stirred at room temperature forone hour.

Isolation as base:

After cooling down to room temperature, the reaction mixture is pouredonto a thoroughly stirred mixture of 200 g of ice, 200 ml of water and20 ml of acetic acid. The precipitate is filtered off with suction andcentrifuged off and is washed with weakly acetic acid water. Furtherpurification is effected by washing with or recrystallizing fromacetonitrile while ensuring that the medium remains weakly acid (aceticacid).

Isolation as hydrohalide:

After cooling down to room temperature, the reaction mixture is pouredonto a thoroughly stirred mixture of 200 g of ice, 200 ml of water and20 ml of concentrated hydrochloric acid (or 47% strength hydrobromicacid). The precipitate is filtered off with suction or centrifuged offand washed with 5% strength hydrohalic acid. Further purification iseffected by washing with a mixture of hydrohalic acid and acetonitrile.Drying takes place in a desiccator over KOH.

A 5.2 Preparation of compounds of the formula (VIIIa)

3 ml of triethylamine are added to a mixture of 20 mmol of a salt of theformula (VI) and 20 mmol of a cycloammonium compound in 50 ml ofdimethylformamide. This is followed by stirring at room temperature forabout 2 hours and working up as described under A 5.1.

A 6. General method for preparing higher polymethines

A 6.1 Preparation of compounds of the formula (IX)

20 mmol of a compound of the formula (VI) and 10 mmol of a dicarboxylicacid (malonic acid, glutaconic acid, piperiylenecarboxylic acid) aredissolved in 50 ml of dimethylformamide. 2 g of finely ground potassiumhydroxide are added at room temperature. The reaction mixture is stirredat room temperature for 4 hours and is worked up as described under A5.1.

A 6.2 Preparation of compounds of the formula (X)

20 mmol of a compound of the formula (VI) and 10 mmol of allyl cyanideare dissolved in 50 ml of dimethylformamide. 2 g of finely groundpotassium hydroxide are added at room temperature. The reaction mixtureis stirred at room temperature for 4 hours and is worked up as describedunder A 5.1.

A 7. General method for preparing quaternized methines

2 mmol of the neutral methine are stirred under nitrogen in the absenceof moisture in 25 ml of 1,1,1-trichloroethane with 4 mmol oftriethyloxonium tetrafluoroborate at from 10° C. to no more than 30° C.for about 16 h. The precipitated crystalline product is filtered offwith suction, washed with mineral acid acetonitrile, methanol and etherand dried under reduced pressure.

The method was applied to the neutral methine dye (43), affording thecorresponding N-ethylmethinecyanine fluoroborate.

In place of 1,1,1-trichloroethane it is also possible to use anhydrousmethylene chloride, nitrobenzene or nitromethane.

The alkylation can also be carried out with trimethyloxoniumfluoroborate, affording the corresponding methylammoniumcyanines.

The directions of A 1. to A 4. were followed to prepare the followingmethine dyes from the corresponding acetonitrile compounds and the C₃ -to C₁₁ units.

DMF=N,N-dimethylformamide

MeCN=acetonitrile

          λ.sub.max     [λ.sub.max ].sup.⊕ ( =      λ.sub.01 and [λ.sub.max ].sup.⊖  Pentamethine     dyes  (= λ.sub.00) λ.sub.02) ( =      λ.sub.00)            (1)      ##STR201##      DMFMeCNCHCl.sub.3 597624 528515 536543      (2)     ##STR202##      DMFMeCNCHCl.sub.3 603625 537544 539548      (3)     ##STR203##      DMFMeCNCHCl.sub.3 654663689 565555560 592582580      (4)     ##STR204##      DMFMeCN 547544 500500 538533      (5)     ##STR205##      DMFMeCNCHCl3 537550 495 524      (6)     ##STR206##      MeCNCHCl.sub.3 607619 505515 565572      (7)     ##STR207##      MeCNCHCl.sub.3 755 570570 617630      (8)     ##STR208##      MeCNCHCl.sub.3 760800 630630 710722      (9)     ##STR209##      DMFMeCNCHCl.sub.3 693680743 630620620 ------      (10)     ##STR210##      MeCNCHCl.sub.3 685743 620625 ----      (11)     ##STR211##      DMFMeCNCHCl.sub.3 672665696 600595605 ------      (12)     ##STR212##      DMFMeCN CHCl.sub.3 665658689 598593599 ------      (13)     ##STR213##      MeCNCHCl.sub.3 670696 588597 ----      (14)     ##STR214##      DMFMeCNCHCl.sub.3 619612634 540520538 577564567      (15)     ##STR215##      DMFMeCNCHCl.sub.3 610609 626 530515520 564550560      (16)     ##STR216##      DMFMeCNCHCl.sub.3 622628646 580575590 580563579      (17)     ##STR217##      DMFMeCNCHCl.sub.3 610642 470475 590579587      (18)     ##STR218##      DMFMeCNCHCl.sub.3 595595625 540540545 535537 547      (19)     ##STR219##      DMFMeCNCHCl.sub.3 623625 550545 573560      (20)     ##STR220##      DMFMeCNCHCl.sub.3 638636657 555535545 575567577      (21)     ##STR221##      DMFMeCNCHCl.sub.3 660684 560555560 583571576      (22)     ##STR222##      DMFMeCNCHCl.sub.3 673664700 620615625 ------           λ.sub.max     [λ.sub.max ].sup.⊕ ( =      λ.sub.01 bzw. [λ.sub.max ].sup.⊖  Heptamethine     dyes  (= λ.sub.00) λ.sub.02) ( =      λ.sub.00)            (23)      ##STR223##      DMFMeCNCHCl.sub.3 695698719 570550 639630      (24)     ##STR224##      DMFMeCNCHCl.sub.3 711 699729 580550 641633      (25)     ##STR225##      DMFMeCNCHCl.sub.3 778775790 580565550 686676           λ.sub.max     [λ.sub.max ].sup.⊕ ( =      λ.sub.01 and [λ.sub.max ].sup.⊖  Heptamethine     dyes  (= λ.sub.00) λ.sub.02) ( =      λ.sub.00)            (26)      ##STR226##      DMFMeCNCHCl.sub.3 810807830 625610615 727718737      (27)     ##STR227##      DMFMeCNCHCl.sub.3 795795802 580560555 727719      (28)     ##STR228##      DMFMeCNCHCl.sub.3 710713739 570570580 610602616      (29)     ##STR229##      DMFMeCNCHCl.sub.3 793785795 590570575 712700715      (30)     ##STR230##      DMFMeCNCHCl.sub.3 810 575560575 725717745      (31)     ##STR231##      DMFMeCNCHCl.sub.3 708712 555526550 674664677      (32)     ##STR232##      DMFMeCNCHCl.sub.3 652643655 560 560570 642633640      (33)     ##STR233##      DMFMeCNCHCl.sub.3 725729749 555540550 665654      (34)     ##STR234##      DMFMeCNCHCl.sub.3 725726744 555540550 665655672      (35)     ##STR235##      DMFMeCNCHCl.sub.3 750794 590565575 676667678      (36)     ##STR236##      DMFMeCNCHCl.sub.3 710704735 640630625 630621640      (37)     ##STR237##      DMFMeCNCHCl.sub.3 738780810 650637650 669659676      (38)     ##STR238##      DMFMeCNCHCl.sub.3 764761790 605565570 673664678      (39)     ##STR239##      DMFMeCNCHCl.sub.3 730727723 590575585 633622620           λ.sub.max     [λ.sub.max ].sup.⊕ ( =      λ.sub.01 and [λ.sub.max ].sup.⊖  Nonamethine dyes      (= λ.sub.00) λ.sub.02) ( =      λ.sub.00)                 (40)      ##STR240##      DMFMeCNCHCl.sub.3 736778 650 653      (41)     ##STR241##      DMFMeCN CHCl.sub.3 765820 630 675      (42)     ##STR242##      DMFMeCNCHCl.sub.3 809850 620620 695715       (43)     ##STR243##      DMFMeCNCHCl.sub.3 881871910 582562570 778           λ.sub.max     [λ.sub.max ].sup.⊕ ( =      λ.sub.01 bzw. [λ.sub.max ].sup.⊖  Undecamethine     dyes  (= λ.sub.00) λ.sub.02) ( =      λ.sub.00)            (44)      ##STR244##      DMFMeCN 1000 590560  915870

Preparation of the optical recording medium

Two 1.2 mm thick polycarbonate disks having a diameter of 120 mm and acentral hole diameter of 15 mm are cleaned with alcohol and coated underclean room conditions with an 0.3 μm thick smoothing layer ofphotopolymer. After curing the photopolymer with UV light, a solution ofdye (43) (=dye III. 108) and 1.3 g of a copolymer of methylmethacrylate/methacrylic acid (70:30) in 200 ml of ethyl acetate waswhirler-coated at 4800 r.p.m. onto the disks. After drying the layerthickness was 0.26 μm. In a vacuum vapor deposition apparatus analuminum mirror was applied to the dye layer in a thickness of 0.03 μm,and was in turn whirler-coated with a 1.2 μm thick protective layer ofpolystyrene from xylene.

The two disks are adhesively bonded together like a sandwich with thecoated sides facing inward but held apart by suitable spacer rings insuch a way that an air gap of 0.4 mm remains. Using an ALGaAs laser(λ=820 nm) mounted on a turntable, individual, approximately 1 μm sizedholes are inscribed in the active layer. The sensitivity of the layer isbetter than 1 nJ/hole; on reading the dots an excellent signal/noiseratio was observed.

We claim:
 1. A methine dye which, in one of its tautomeric forms,conforms to the formula ##STR245## where each Y¹ is the same ordifferent and is selected from the group consisting of cyano,trifluoromethyl, nitro, carbo-C₁ -C₁₂ -alkoxy, phenylsulfonyl orphenylsulfonyl which is monosubstituted or disubstituted by C₁ -C₁₂-alkyl, C₁ -C₁₂ -alkoxy, halogen and cyano,Y² is in each case,independently of the others, hydrogen, cyano, halogen, C₁ -C₆ -alkyl, C₅-C₇ -cycloalkyl, phenyl, or pyridyl, R is hydrogen, C₁ -C₂₀ -alkyl, C₇-C₁₀ -aralkyl or β-hydroxyethyl, and n is 1, 2, 3, 4, 5 or 6, and thegroups ##STR246## are identical or different and are selected from thegroup consisting of ##STR247## wherein R₁ -R₆, R₁₀ and R₁₁ are each,independently of one another, hydrogen, halogen, CN, CF₃, nitro, C₁ -C₄-alkyl, C₁ -C₄ -alkoxy or phenyl which may be substituted by halogen, C₁-C₄ -alkyl, C₁ -C₄ -alkoxy, CN, CF₃ or NO₂, only one nitro group beingpresent per radical D.
 2. A methine dye according to claim 1, wherein Y¹is cyano.
 3. A methine dye according to claim 1, wherein the number ofsubstituents on D is, per D 0, 1 or
 2. 4. A methine dye according toclaim 1, wherein said D groups are identical or different and areselected from the group consisting of: ##STR248##
 5. A methine dyeaccording to claim 1, which is: ##STR249##
 6. A methine dye according toclaim 1, which is: ##STR250##
 7. A methine dye according to claim 1,which is: ##STR251##
 8. A methine dye according to claim 1, which is:##STR252##
 9. A methine dye according to claim 1, which is: ##STR253##10. A methine dye according to claim 1, which is: ##STR254##
 11. Amethine dye according to claim 1, which is: ##STR255##
 12. A methine dyeaccording to claim 1, which is: ##STR256##
 13. A methine dye accordingto claim 1, which is: ##STR257##
 14. A methine dye according to claim 1,which is: ##STR258##
 15. A methine dye according to claim 1, which is:##STR259##
 16. A methine dye according to claim 1, which is: ##STR260##17. A methine dye according to claim 1, which is: ##STR261##
 18. Amethine dye according to claim 1, which is: ##STR262##
 19. A methine dyeof claim 1, having the following formula: ##STR263##